


Thin Blue Line: Bang Bang

by team_mcmahon86



Series: Thin Blue Line [1]
Category: Chicago PD (TV)
Genre: F/M, Gen
Language: English
Status: In-Progress
Published: 2019-03-05
Updated: 2019-09-16
Packaged: 2019-11-12 09:40:28
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 4
Words: 3,510
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18008510
Author URL: https://archiveofourown.org/users/team_mcmahon86/pseuds/team_mcmahon86
Summary: Libby Reagan's personal and professional life are in shambles until the day she gets assigned to work murder case with Intelligence and things start changing





	1. Introduction

Thin Blue Line.   
This is the first volume of series and it's going to mention the Reagan family from Blue Bloods but they aren’t going to be in this as much. And it's also going to kind of be tied into Paradise Undone and Under Suspicion which is going to be a Law Order SVU story and Dirt Bag which is a NCIS story and Things Nightmares are Made Of which is a Criminal Minds story. If you can’t tell I love, love crime shows and I have spent the last week I have been sick binge watching and perfecting the storylines for them.  
Also for this series, Jay and Erin were never together for long, and she still goes to New York with the FBI leaving Jay alone. I am going to try and follow along as much as I can with everything after season 3 of Chicago PD.   
The first few chapters take place in the start of season 2.   
Summary: Libby Reagan’s life was in shambles, the only bright side was her being made detective. And now she and members of the Intelligence Unit are trying to catch a duo of serial killers.   
Rated M for Mature.  
Eventual Jay Halstead/OFC  
**  
One  
Socialite Murders   
**  
“Oh, come on Reagan! You have been in Chicago for how long and you still aren’t a Chicago fan?” Billy Arden asked his partner who shrugged her shoulders and moved the rickety wood rolling chair she was sitting in to side to side. “I am a New Yorker through and through what can I say?” Libby Reagan grinned, still moving the chair back and forth making it creak as she did. “Yeah but you live in Chicago now! You should adapt to being a Chicago fan! Black Hawks, White Sox, Cubs, Bears, Bulls” He argued pointing his finger at her. She shrugged her shoulders, he wasn’t the first person that told her that and he wasn’t going to be last but she found it fun to argue with him about it. And it passed the time on slow days like this. ““Yankees, Mets, Jets, Rangers and Knicks. And at least the Yankees have won a title in the last 100 years.” Billy inhaled sharply as if she had slapped him, “You just had to bring that up didn’t you?” His partner grinned almost gleefully as she nodded her head.   
“Reagan! Arden! You are up!” Sargent Hardy said coming out of his office, “There is a murder south of Halstead.” “Well aren’t we lucky?” Libby said standing up and shrugging her well worn leather jacket on, “They didn’t kick it up to intelligence.” “Oh someone is still jealous.” Billy muttered following her lead. “Not jealous, just annoyed. He dropped me like a hot potato as soon as Erin showed interest.” Libby returned as she held the car keys out to him. “Didn’t your brothers ever teach you not to date cops?” “Nah. They would rather have me date cops then date a firefighter.” Billy laughed as he tossed the keys to the sedan up in the air and catching them quickly. There had been a month and half after she first moved to Chicago that she was hot and heavy with the Squad 3 leader. It was hot, heavy and quick. Something that didn’t seem like Libby at all.  
And then she was reintroduced to Jay Halstead, a brother of a friend that she had in New York, Will had told her that she that they would be just perfect for each other. And that turned out to be false. Especially when Jay dumped her for his partner Erin, Billy and Leslie Shay had to peel Libby off of the floor. It was not a pleasant experience.  
“Besides, not having a boyfriend is liberating, it’s like not shaving your legs or wearing a bra.” She grinned as they walked down the staircase to the lobby stepping aside as several other detectives climbed the stairs, shooting Libby a weird look for her comment.

“You say that now then your sister will call you and you will have a freak out moment then you are going to be back where you started dating the first guy that you see.” “Shut up Arden.” He laughed, they both knew that he was right and he didn’t want to be the one that to peel her off of the floor like he did when her ex husband left her. “Look I promise, I won’t go dating the first guy I see if Erin starts in on me if you promise to layoff of the whole Jay thing.” He groaned before he nodded his head once, “Fine.”   
**  
“Hey Lib.” Jay Halstead greeted as he and Antonio Dawson joined her on the sidewalk outside of the diner were the murder took place. “Antonio.” Libby returned ignoring Jay’s greeting completely. “What happened here?” the older detective asked. “A girl Amanda Shore, from Lincoln Park was assaulted and killed. The perp took her wallet and jewellery. The girl was 17, planning a senior trip to Europe with her best friends. And this guy killed her.” She explained, “Arden is in there right now talking to them.” “And why are you out here?” Jay asked. “Weak stomach.” She returned. “Well we are here to help. Tell us what you want us to do.”


	2. Notifications

Two: Notifications 

“We have to make the notifications to Amanda’s family.” Libby said tapping her fingers against her hips as she started to pace, “they snatched another girl from what I heard before I came out here.” “The other girl’s name is Kellie Nichols. Also 17 from Lincoln Park.” Arden said as he came out of the diner, “their friends said that Kellie and Amanda went to the bathroom and when Sybil went to check on them she found the body and the trail of blood.” “Did they notice anyone watching them?” Antonio asked. “No. They are pretty shaken up.” “Of course they are.” Libby said turning on her heel and looking at the trio, “their friend was butchered and another is missing. And they are just 17 years old. God when I was 17 all that mattered was getting into college and playing softball. No kid should ever, ever have to see that.” “You are right Libby, but this is our job to find the bastards that did this.” Antonio said, “I want you and Jay to go notify the families. Arden and I will stay here and finish with the crime scene.”   
Arden nodded his head agreement, he knew things would get ugly with Jay and Libby being together but he knew Antonio was right, Libby was better with talking to people then analyzing crime scenes.   
“Fine but I am driving.” Libby said holding her hand out to Arden for the keys, which he handed over to her with a smirk. “Don’t do anything I wouldn’t do.” “Never.” She grinned, “Come on Halstead.” “What wouldn’t do to be a fly in that car ride.” Arden muttered before going into the diner again, Antonio trailing behind him chuckling under his breath.   
He had heard all about what happened between the two from his younger sister, Gabby who was good friends with Libby and agreed with the statement that Jay and Libby would make a good girlfriend. And he had even went as far to agree with Libby’s silent treatment. The way Jay ended their relationship was the easy way out. And not like him. When Erin was around he was different. And maybe being around Libby will help bring him back to the Halstead they all knew.  
**  
The car was silent as Libby drove to Lincoln Park and it was an uncomfortable silence, it felt like you could cut the tension with a butter knife. And it wasn’t something that Jay was used too. When he first met Libby, she was different from the girls he meet in Chicago or even New York. She was vibrant, confident, loyal, full of sass. And it was something that brought him. It was like a moth to the flame. And in his experience it doesn’t happen very often. In fact it only happened to him other one time and that was with Erin, his current partner and on again, off again girlfriend.   
“Look Lib.” He started unable to handle the silence anymore. “Jay, don’t. Please.” She said glancing at him out of the corner of her eye. “You made your choice. You wanted her, fine. We were just having fun right?” “No, I never wanted to hurt you but when Erin.” “I don’t want to hear it okay Jay? You wanted her now you got her.” She said throwing the car into park in front of the brownstone house where Amanda Shore lived. “Let’s just deal with this.”   
***   
“Hi Mrs. Shore, I am Detective Reagan and this Detective Halstead with Chicago police department.” Libby said after a blonde woman opened the door. “Richard!” She called quickly behind her before stepping away from the door, “come in please.” Jay nodded his head before stepping back and letting Libby step into the house first.   
A tall man with salt and pepper hair came down the stairs and to his wife’s side. “What’s going on?” “I don’t know but these are detectives with the Chicago Police Department.” “We are sorry.” Jay started having followed Libby into the hallway, “but your daughter Amanda was killed.” “What? No there is some sort of mistake.” Richard said as he pulled his wife into his arms. “It is I am so sorry,” Libby said reaching into her jacket pocket and pulling out an evidence bag that held her smashed cell phone and a necklace with a diamond pendant hanging from the middle of it, “These were found by her body.” “No. No.” The trembling woman muttered as she started sinking to the ground. Libby shoved the plastic bag into Jays hand and went over to the couple and grabbed ahold of her forearm to help keep her upright. “I won’t lie and say that I know how this pain feels, I have never lost a child but my older brother was killed in the line of duty by dirty cops. It will get better.” The woman looked up at her with wet green eyes. “And I can promise you this. We will catch this son of a bitch that did this.” “Did you catch the cops that killed your brother?” “They were caught yes.” Jay answered, he had heard the whole story from her one night. “Okay.” The woman muttered freeing a trembling hand from her husband and squeezed Libby’s hand. “We will be in touch soon.” The former New Yorker said softly squeezing her hand back. “Thank you.” Richard said before leading his wife away.   
**  
“You shouldn’t have promised that.” “I know that Jay.” She snapped as she lowered her sunglasses down over her eyes, “It just slipped out. And we will catch this son of a bitch one way or another.”   
**  
A boy in his early twenties with a scar that ran from his temple to chin smirked watching the two detectives get into the dark sedan. There was no way they were going to catch him and his partners. They had learned from the best. He still has been running rampant years after he started his killing spree and there was no way in hell that they could catch on to them. They were too good and too smart for them.


	3. Nerves

Three: Nerves

"Hey Lib! Long time! Everything okay?" Danny asked after seeing that Libby's name was flashing on his phone. "Not really, I caught a murder case and it kinda reminds of the one that Joe got before he moved to warrants." "You mean the rich kid murder case?" "Yeah, they took one girl then killed the other one." "Jesus, how the hell did you catch that case?" "I don't know. Do you still have Joe's old files?" "Yes, I will have Linda get them. I am going to come out." "Danny, I don't need you too." "I don't care, I will clear it with Gormley and I will be there soon. If it's anything like Joe's case, these guys are just getting started. And you and Arden will need all the help you can get." "It's not just us. Its Intelligence too." "Is that Jay guy working it too?"

Libby was silent.

And in a instant Danny was furious, he of course had heard what happened between Libby and Jay, and it took everything in him not go to Chicago and defend his sister. But her twin brother and Linda talked him out of it. Libby could defend herself. Or so they thought. "Damn it Libby. I wish you would have come back home." "And live with Dad and Grandpa and have to be reminded every other day that it was my fault that Michael was killed? No thank you."

A male voice in the background said something to his sister and she replied quickly, "I got to go Danny, we need to get upstairs. I guess I will see you in a couple of hours." 

Danny opened his mouth to reply but was cut off by the dial tone.

**

"What's with the look Reagan?" Arden asked they followed Antonio up the stairs. "Danny is coming out with Joe's flies and he isn't happy that Jay and I are working together." "How did they find out about it?" "Jamie. He found out from me and he told the damn family."

"That's your own fault telling your twin." "Hey! I had no choice! He knew something was wrong!" "Perks of having a twin right?" Antonio asked turning to look at her. "Yep. And I always know when something is wrong with him. I knew when he and Syd broke up. And he didn't even have to tell me. We just know." Libby returned as they climbed the last steps into the intelligence bullpen. "What do you guys know?" Voight asked as Carlie Rhodes waved her hand at her friend smiling brightly.

The former New York Detective returned it before looking at Voight and putting her hands on her hips, her defenses jumping seeing Erin sitting across from Jay. She hadn't been face to face with Erin since Jay left her for his partner. "I talked to my brother Danny, he has our older brother Joe's case files. He worked a case like this before he was transferred to warrants. They target the daughters of influential members of society." "And Danny is coming out." Arden added causing Libby to glare at him. "He thinks we need all the help we can get." "Joe wouldn't talk about the case, thought I was too innocent to hear about the lengths some people would go to hurt another person."

Erin fought back a smirk, she could tell that Libby was far too innocent and pure to be a cop. Let alone have her detective's badge. She always thought that Libby's family got her to where she was at. Her father was the police commissioner and her grandfather was the commissioner before and her three brothers were also cops and her sister was also an ADA. She had things handed to her. And this was just the starts of it.

"I do know that it's only a matter of time before they strike again." Libby said, "And it will only get worse." Her fingers were tapping nervously against the material of her jeans, normally she wasn't a nervous person but being there and seeing the man that she had wanted with his girlfriend and Hank Voight who was notorious for being a hardass. Made her nervous.


	4. Big Brother To The Rescue

Four: Big Brother To The Rescue.   
“Excuse me?” Danny Reagan asked as he came into the 21st district and up to the desk where Trudy Platt was sitting. She glanced up at him and then back at the paperwork that was sitting in front of her. “I am here to see Detective Reagan.” Platt looked back up surprised, she knew that Libby and Arden were working out of the 21st district with the Intelligence for the time being and was curious to see what this guy wanted with them.   
She wouldn’t admit it out loud especially with Erin working in the same district but she had a soft spot for Libby. The first time she actually met the younger girl she actually smiled at her and didn’t act like she was put off by her attitude towards people.   
“Danny!” Libby’s voice said from the staircase shaking Platt out of her thoughts. “Hey kiddo!” Danny returned his own smile clear in his voice as he gathered up the files and went over to where his sister was standing on the stairs. The desk sergeant watched the two siblings interact with a small smile twitching at her lips before Libby turned to look at her. “Do you mind buzzing me back up?” She asked a smile playing on her lips. Platt nodded her head and pressed the button on the underside of the counter. “Thanks Sarge.” Libby said before pulling the gate open and letting Danny go in front of her.   
For the first time in a long time she was glad that her older brother was there to play referee and protect her. She felt like she needed it with Erin being there and being around.   
“Anything new?” Danny asked as they climbed the stairs. He wanted to ask about Jay but he knew he had to lead up to the bullpen. “Not yet. A couple of the detectives went to meet with their CI’s. I stayed behind with Mouse, their IT guy to look through files.”  
“And?”  
“And I wanted to talk to you before you met everyone else. Erin, Jay’s girlfriend is here. She is one of his partners. I wanted to ask you to please, please don’t do anything to piss her off.”  
The oldest Reagan sibling rolled his eyes before squeezing her sister’s shoulder, “Fine, I will try and play nice.” “Thank you.” She muttered before climbing the rest of the stairs, “Mouse this is my older brother Danny. Danny this is Mouse.” “Greg.” Mouse clarified, “I feel like I know you and your other siblings with as much as Libby talked about you.” Seeing Danny’s confused look, Libby grinned and sat down in the rolling chair that was opposite of him, “I use to write him and Jay when they were overseas.”  
“Got it.” Danny said before sitting next to his sister and flipping open the file, that sounded like Libby, writing letters to keep in touch. He still had all the letters that she had sent him while he was stationed overseas. “She’s a good kid.” Mouse teased causing Libby to throw a balled up piece of paper at him. “Shut up Mouse.”   
**  
“There’s rumors going around that they want to go after one of the detectives working the case.” Mikey Matthews said as he nervously lit a cigarette. “Which one?” Jay asked as Adam started pacing next to him, there was only a handful of detectives working the case. And it could be either one. “The one that was with you doing notifications.” All the color rushed out of Jay’s face, “Reagan?” “Yeah, her. From what I heard, her brother had the case before her and caused a bunch of problems for them, they may be going after her for revenge.” “Son of.” Jay muttered his breath as he ran his hand over his face. “We need to get back to the station and let them know what’s going on.” Adam said lowly before nodding his head at Mikey who nodded back and disappeared down the dark alleyway that he came.   
***  
“Why aren’t you taking her off of this Hank?” Erin asked as the leader of the Intelligence Unit drove towards the station again. “Because, the higher ups ordered me not too.” “She isn’t made to be a police officer. She shouldn’t have gotten her detectives badge.”  
“Is this because she dated Jay before you or is it because you are jealous that she is showing you up and he still paying attention to her?” Erin was silent, it was all of it. But she wasn’t going to admit that out loud.   
And especially to Hank.  
“We will solve this case and she and Arden will be back at their own district. And that will be it.”   
**  
Jay and Adam were the first two back from meeting with their cis and were in a hurry to go up and meet the rest. Especially since there was a rumor going around that Libby was in the sights for the perps. And for Jay he wanted to make sure that Libby was okay. He trusted Mouse enough to keep an eye but he wanted to keep an eye on her himself. He didn’t know if it was because he felt guilt for hurting her or if he still had feelings for her. Either way he wanted to be there with her.


End file.
